NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Temporal variations of the anomalous oxygen componentData from the cosmic ray experiment on Voyagers 1 and 2 was used to examine anomalous oxygen in the time period from launch in 1977 to the end of 1981. Several time periods were found where large periodic (typically 26 day) temporal variations of the oxygen intensity between approximately 5 - 15 MeV/nuc are present. Variations in intensity by up to a factor of 10 are observed during these periods. Several characteristics of these variations indicate that they are not higher energy extensions of the low energy particle (approximately 1 MeV/nuc) increases found in many corotating interaction regions (CIR's). Many of these periodic temporal variations are correlated with similar, but much smaller, recurrent variations in the 75 MeV proton rate. Voyager 1 and Voyager 2 counting rates were compared to estimate the local radial gradient for both the protons and the oxygen. The proton gradients during periods of both maximum and minumum fluxes are consistent with the overall positive radial gradients reported by others from Pioneer and near-Earth observations, supporting the view that these variations are due to local modulation of a source outside the radial range of project measurements. In contrast, the oxygen gradients during periods of maximum proton flux differ in sign from those during minimum proton fluxes, suggesting that the origin of the oxygen variations is different from that of the protons.
Document ID
19840005031
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Cummings, A. C.
(California Inst. of Tech. Pasadena, CA, United States)
Webber, W. R.
(New Hampshire Univ.)
Date Acquired
August 12, 2013
Publication Date
November 1, 1983
Publication Information
Publication: JPL Solar Wind Five
Subject Category
Solar Physics
Accession Number
84N13099
Funding Number(s)
CONTRACT_GRANT: NAGW-200
CONTRACT_GRANT: NGR-05-002-160
CONTRACT_GRANT: NAS7-918
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
No Preview Available